Process of making chain links



Aug. 9, 1938. E, w. TAYLOR ET AL PROCESS OF MAKING CHAIN LINKS Filed March 26, 1938 INVENTORS 7Zy/w' p fel i'salz Mm.

Patented Aug. 9, 1938 UNITED STATES PATENT OFFICE PROCESS OF MAKING CHAIN LINKS Illinois Application March 26, 1938, Serial No. 198,171

3 Claims.

This invention relates to the manufacture of metal chains and, more particularly, to the re moval from a welded chain link of the bulge or fin which normally is formed in the welding operation.

For certain purposes the presence of this bulge or fin is undesirable and, therefore, must be removed. For example, if the chain is to be used in connection with sheaves or pocket wheels the external dimensions of each link should be approximately uniform and any protuberance such as a fin would prevent the link from fitting into the pocket or sheave. Furthermore the sharp projection of such fins are apt to injure workmen handling the chain.

It has heretofore been more or less common practice in the art to remove all or a major portion of the fin by clamping a swaging die or similar tool over the weld, while the fin is still in a plastic state, to conform the fin to the size of the adjacent link stock. However, pressing the fin not only tends to distort the link but also results in a partial displacement of the weld. Furthermore such operation drives into the Weld some of the oxidized metal of the fin thereby weakening the weld.

The principal object of the present invention is to provide a simplified method of removing the undesirable portion of the fin from a welded chain link in such manner that none of the metal comprising the fin is pushed into the weld.

A further object of the invention is to provide means for removing the fin in such manner that no swaging operation is necessary.

These and other objects will more fully appear from the following detail description of the invention and with reference to the accompanying drawing, wherein:

Fig. 1 is a perspective of a chain assembly during the chain manufacturing operation, showing also the relative position of a fin removing device.

Fig. 2 is a perspective of a freshly welded link with the fin removing device in position to remove the fin.

Fig. 3 is a perspective showing the relative position of the parts immediately after the fin has been removed.

Fig. 4 is a perspective of the link shown in Figs. 1, 2 and 3 with the undesirable portion of the fin removed and the fin removing device returned to its initial position.

Referring to the drawing, Fig. 1 illustrates a section of a partially completed chain, reference characters l and II designating finished links, reference character l2 designating a freshly welded but untrimmed link and i3 and I4 designating unwelded links, the links of the chain being welded and trimmed in the direction indicated by the arrow.

The link I2 is rigidly supported, for purposes of welding and also for the purpose of trimming according to the present invention, by any suitable means such as two pairs of link holders or wedges I5, l6 and l1, l8 adapted to fit into links H and I3, respectively, and to abut against link I2. The wedges are adapted not only for movement in and out of wedging engagement but are also adapted, for a purpose to be presently described, for movement along the longitudinal axis of the links H, I 2 and I3 as indicated by the arrow.

The link I2, as shown; has been freshly welded by an electric welding operation resulting in a bulge or fin Hi. It should be borne in mind that during the operations hereinafter described the metal adjacent the fin I9 is, while the fin is being removed, in a plastic state.

Immediately below the link I2 is a fin trimmer 20 formed at its upper end with a U-shaped pocket or groove 2|, the depth and width of which substantially correspond to the diameter of the link stock from which link 12 is formed. The thickness of the trimmer is preferably no greater than necessary for proper strength and rigidity. The trimmer 20 is adapted to be moved vertically to engage the link l2 adjacent the fin l9. As soon as the link I2 is welded and the electrodes (not shown) are removed, the trimmer 20 is moved into the position illustrated in Fig. 2. The supported link I2 is then drawn or pulled, by suitable means (not shown) in the direction indicated by the arrows whereby the welded portion of the link is drawn through the groove 2|, the edges of which thereby shear off all of the fin except that on the inside surface of the link, thus reducing the outer portions of the fin to approximately the same contour as the adjacent link stock, as indicated in Fig. 3. In other words, that portion of the fin is sheared off. The trimmer 20 is then returned to its initial position as shown in Fig. 4.

Although various modifications and variations may be made without departing from the scope of the present invention it is preferred if best results are to be obtained, to pull rather than push the fin through the trimmer. It has been found that if it is attempted to push the fin through the trimmer there will be a tendency to increase the width of the link at the point of the weld, which is still in a relatively plastic state,

thus either blocking the trimmer or displacing the weld. By pulling the link through the trimmer on the other hand, a longitudinal tension is exerted on the link and the tendency to increase the width of the link at the point of the weld is avoided. As a matter of fact, with the method of the present invention, any resistance to the passage of the fin through the trimmer tends to decrease rather than increase the diameter of the link.

It will be understood, of course, that the above description constitutes only one cycle of the series of operations performed in manufacturing the chain. Obviously, as soon as the undesirable portion of the fin IS on link I2 is removed, the wedges are removed and the chain moved to place unwelded and untrimmed link I3 in the position occupied by link ii in Fig. 1.

It will also be understood that the size of the groove 2| on trimmer 20 will not correspond exactly to the diameter of the link stock but will be slightly larger (for example ,6 inch larger) to permit freedom of movement therethrough and avoid possible gouging of the weld itself should the groove and the link be slightly out of proper alignment. Furthermore, if the link is formed by welding together two U-shaped portions, a. duplicate trimmer could be providec' to remove both fins simultaneously.

It is the intention to cover all modifications or equivalents within the scope of the folowing claims.

We claim:

4 1. Method of removing the major portion of the fin from a welded link which consists in subjecting the major portion of thefin, while the samev is in a plastic state, to passage through a curved opening substantially corresponding to the normal size and contour of the external portion of the link stock adjacent the point of the weld so as to in a single operation round and shear the" link to finished form.

2. Method of removing the major portion of 3. Method of removing the major portion of the fin from an electrically-welded link which comprises drawing the hot fin, without removing the link from the position in which it was supported for the welding operation, through a curved opening substantially conforming to the size and con.-

tour of the link stock adjacent the weld whereby" the external portion of the link is curved and the adjacent opposite sides tangentially sheared in a single operation.

EDWARD W'IN'I'HROP TAYLOR. CARROLL PETERSON. 

